Synthetic resin molded material and method for its production

ABSTRACT

A synthetic resin molded material characterized in that a thin film made of an oxide of at least one metal selected from the group consisting of Si, Zr, Ti, Ta, Hf, Mo, W, Nb, Sn, In, Al and Zn, is formed by a dry method on a synthetic resin substrate having hydrophobicity, and a method for its production.

TECHNICAL FIELD

[0001] The present invention relates to a synthetic resin moldedmaterial and a method for its production.

BACKGROUND ART

[0002] Heretofore, a synthetic resin substrate having hydrophobicity hassometimes had a trouble attributable to the hydrophobicity. For example,a fluorine-containing resin film as a typical example of a syntheticresin substrate having hydrophobicity, is excellent in transparency,durability, weather resistance, antisoiling property, etc., and byvirtue of such characteristics, it has been used as a film for anagricultural or horticultural house instead of a vinyl chloride resin.However, when a fluorine-containing resin film is used for anagricultural or horticultural house, moisture condensation is likely toform on the inside surface of the film as the film has nohydrophilicity, whereby problems are likely to result such thatsunlights required for the growth of plants tend to be blocked, ordeposited water drops are likely to drop directly on crop plants insteadof flowing in the form of a water film on the film surface, to presentadverse effects.

[0003] To solve such problems, as a method for imparting hydrophilicityto the surface of a synthetic resin substrate, a coating method hasheretofore reported in which a mixture of a silica-type sol and asurfactant, is coated on the resin surface, followed by drying to imparthydrophilicity (e.g. JP-A-62-179938, JP-A-5-59202 and JP-A-5-59203).

[0004] However, with the hydrophilic film obtained by this method, thehydrophilicity does not last for a long period of time, and in a casewhere it is used for a synthetic resin which has a long useful life likea fluorine resin film, there has been a problem that costs and time willbe required, as it is necessary to carry out recoating periodically.

[0005] The present invention is intended to solve the above-mentionedproblems of the prior art and to provide a synthetic resin moldedmaterial having adequate hydrophilicity, whereby the hydrophilicity willlast for a long period of time.

DISCLOSURE OF THE INVENTION

[0006] The present invention provides a synthetic resin molded materialcharacterized in that a thin film made of an oxide of at least one metalselected from the group consisting of Si, Zr, Ti, Ta, Hf, Mo, W, Nb, Sn,In, Al, Cr and Zn is formed by a dry method on a synthetic resinsubstrate having hydrophobicity.

[0007] In the present invention, it is important to form the thin filmmade of an oxide of at least one metal selected from the groupconsisting of Si, Zr, Ti, Ta, Hf, Mo, W, Nb, Sn, In, Al, Cr and Zn by adry method, whereby a desired synthetic resin substrate havinghydrophobicity can effectively be made hydrophilic.

[0008] The above treatment to impart hydrophilicity is to modify thehydrophobic synthetic resin surface to be hydrophilic. As a result, adrop flowing property (a property to let water drops deposited on thesurface flow), an antifogging property (a property to prevent fogging bymoisture condensation), an anti-mist property (a property to prevent amist attributable to water drops deposited on the film surface), anantistatic property (a property to prevent electrification of staticelectricity), a wettability (a nature to be readily wetted) or the likewill be improved.

[0009] The thin film of an oxide to be used in the present invention, isnot particularly limited so long as it is an oxide of at least one metalselected from the group consisting of Si, Zr, Ti, Ta, Hf, Mo, W, Nb, Sn,In, Al, Cr and Zn.

[0010] It is preferably a thin film made of an oxide of a metalcontaining at least Si, since it is thereby possible to obtain highhydrophilicity. This is believed to be attributable to the fact that Sipresent on the outermost surface of the thin film layer and moisturepresent in the atmosphere will bond to form a highly hydrophilic SiOHstate.

[0011] Specific examples of the oxide of a metal containing at least Si,include oxides comprising SiO₂, oxides of Si and Zr, oxides of Si andTi, oxides of Si and Ta, oxides of Si and Nb, oxides of Si and Sn,oxides of Si and Zn, or oxides of Si, Sn and Ti, as the main components.

[0012] From the viewpoint of the initial hydrophilicity, the durabilityof hydrophilicity for a long period of time and the material cost, anoxide comprising SiO₂ as the main component is preferred.

[0013] From the viewpoint of the initial hydrophilicity, the durabilityof hydrophilicity for a long period of time, the adhesion to thesubstrate and the productivity, oxides comprising oxides of Si and Sn,oxides of Si and Zr, or oxides of Si and Ti, as the main components, arepreferred. Particularly preferred are oxides comprising oxides of Si andSn as the main component.

[0014] Further, with a view to providing a photocatalytic function so asto provide an effect for decomposing or preventing deposition of astain, by irradiation of sunlight, against deposition of a stain whichis considered to be one of factors to prevent the long lasting effect ofhydrophilicity, oxides comprising oxides of Si and Sn, oxides of Si andTi, or oxides of Si, Sn and Ti, as the main components, are preferred.

[0015] From the viewpoint of providing various properties including theabove-mentioned drop flowing property, the thickness of the thin film ofan oxide in the present invention is preferably at least 3 nm. Further,from the viewpoint of maintenance of visible light transmittance,maintenance of flexibility of the synthetic resin substrate and adhesionto the substrate, the thickness is preferably at most 100 nm, morepreferably at most 30 nm.

[0016] In a case where the thin film of an oxide in the presentinvention contains at least Si, the proportion of Si is preferably suchthat Si is from-20 to 80 atomic %, more preferably from 30 to 70 atomic%, to the total metals.

[0017] By adjusting the proportion of Si within the above range, it ispossible to obtain effects such that 1) by the effect of contained Si,the refractive index of the oxide film can be properly made small, andit is possible to obtain a synthetic resin molded material having adesired color, 2) by the effect of metal components other than Si, theabove-mentioned various properties including the drop flowing propertycan be obtained even when the oxide film is made thin, and 3) when adirect current sputtering method is employed as a film forming method,arching can be prevented by using an alloy target having a compositionalrange similar to that of the oxide film.

[0018] The contact angle to water of the oxide film tends to increase asthe time passes from immediately after the film formation. However, thelarger the proportion of Si (for example when Si is at least 50 atomic%), the smaller the change with time of the contact angle to water.

[0019] On the other hand, in a case where an alloy target is employed,if the proportion of Si increases, the film-forming speed tends todecrease. Accordingly, from the viewpoint of the productivity, Si ispreferably at most 70 atomic %.

[0020] In the present invention, the method for obtaining the thin filmof an oxide is not particularly limited so long as it is a dry method.With the dry method, the film can be made uniform, and the adhesion ofthe formed film to the substrate is high, as compared with a wet system.Accordingly, the dry method is one of important requirements foraccomplishing the object of the present invention.

[0021] The dry method may, for example, be a vacuum vapor depositionmethod, a sputtering method, a CVD method or an ion plating method.Particularly preferred is a sputtering method, since it is excellent inthe productivity and is widely used on an industrial scale, and it ispossible to obtain by the method a film which is very dense and has highadhesion to the substrate, in a uniform film thickness.

[0022] The sputtering method may be a direct current sputtering methodor a radio frequency sputtering method. A direct current sputteringmethod is preferred, since it is thereby possible to form a filmefficiently at a high film forming speed on a substrate having a largesurface.

[0023] As an example of a film of the oxide comprising SiO₂ as the maincomponent, a thin film made of SiO₂ may be mentioned. The thin film madeof SiO₂ can be obtained by forming a film by a radio frequencysputtering method in an oxygen-containing atmosphere using a Si target.It can also be obtained by forming a film by a radio frequencysputtering method in an oxygen-free atmosphere using a SiO₂ target.Further, it can be obtained by a direct current sputtering methodwherein an intermittent negative direct current voltage is applied tothe target, instead of the radio frequency sputtering method.

[0024] The power density to the target during sputtering is usually from1 to 20 W/cm², and the gas pressure is usually from 1 to 10 mTorr,preferably from 2 to 6 mTorr.

[0025] As an example of the film of oxides comprising oxides of Si andSn as the main components, a thin film made of oxides of Si and Sn maybe mentioned. The thin film made of oxides of Si and Sn can be obtainedby forming a film by a reactive sputtering method in anoxygen-containing atmosphere using a target of a mixture of Si and Sn.

[0026] In a case where the target of a mixture of Si and Sn is used, itis possible to use a usual direct current sputtering method from such areason as improvement of the electrical conductivity of the target, andthe film forming speed can be increased, as is different from theabove-mentioned Si target. Here, by adopting a method of applying anintermittent negative direct current voltage to the target, it ispossible to effectively suppress arching during the film formation, toincrease the applied power and to maintain a high film-forming speed fora long period of time. Further, the covering rate over the surface ofthe resin substrate is improved, whereby the minimum film thickness toprovide the water dropping property will decrease, which is advantageousalso from the viewpoint of the productivity and the economicalefficiency.

[0027] Similar effects can be obtained also in a case where a targetcomprising Si and at least one other metal selected from the groupconsisting of Zr, Ti, Ta, Hf, Mo, W, Nb, In, Al, Cr and Zn, is used.Especially when a target of a Si—Sn type metal is used, the film formingspeed is high, and the productivity is excellent.

[0028] The above-mentioned target made of Si and Sn may be in the formof a mixture or in the form of an alloy. For example, a target of amixture of Si and Sn can be obtained by molding a mixture of Si and Snby a CIP method (a cold isotropic press method) or a hot press (amolding press at a temperature immediately below the melting point ofSn).

[0029] The synthetic resin substrate having hydrophobicity to be used inthe present invention is not particularly limited, and a thermoplasticsynthetic resin having hydrophobicity or a thermosetting synthetic resinhaving hydrophobicity can be used.

[0030] The thermoplastic synthetic resin may, for example, be afluorine-containing resin, an acrylic resin, a polycarbonate resin, apolyester resin, a polyamide resin, a vinyl chloride resin, an olefintype resin, a polyacetal resin, a polyether imide resin, a polyethersulfone resin, a polyether ketone resin, a polyphenylene sulfide resin,a polysulfone resin, a polyallylate resin, a polyethylene naphthalateresin, a polymethylpentene resin, an ABS resin, a vinyl acetate resin ora polystyrene resin.

[0031] Among these, a fluorine-containing resin, an acrylic resin, apolycarbonate resin, a polyester resin, a polyamide resin, a vinylchloride resin and an olefin type resin are preferred from the viewpointof transparency and moldability. Particularly preferred are afluorine-containing resin, an acrylic resin, a polycarbonate resin and apolyester resin.

[0032] Among them, a fluorine-containing resin is particularlypreferred, since it is excellent in transparency, durability, weatherresistance and stain-proofing property, and it undergoes no modificationeven during film formation in an oxygen-containing atmosphere. Further,it is considered that since the resin itself is expensive, it deservesfor a dry surface treatment, the treating cost of which is relativelyhigh.

[0033] Here, the fluorine-containing resin is meant for a thermoplasticresin containing fluorine in the molecular structure of the resin.Specifically, it may, for example, be a tetrafluoroethylene type resin,a chlorotrifluoroethylene type resin, a vinylidene fluoride type resin,a vinyl fluoride type resin or a composite of these resins. Particularlypreferred is a tetrafluoroethylene type resin from the viewpoint ofhydrophobicity.

[0034] Specifically, the tetrafluoroethylene type resin may, forexample, be a tetrafluoroethylene resin (PTFE), atetrafluoroethylene/perfluoro (alkoxyethylene) copolymer (PFA), atetrafluoroethylene/hexafluoropropylene/perfluoro (alkoxyethylene)copolymer (EPE), a tetrafluoroethylene/hexafluoropropylene copolymer(FEP) or a tetrafluoroethylene/ethylene copolymer (ETFE).

[0035] Among them, PFA, ETFE, FEP or EPE is preferred from the viewpointof moldability. Particularly preferred is ETFE, since it has mechanicalstrength durable for use outdoors for a long period of time. ETFE is theone composed mainly of ethylene and tetrafluoroethylene and a smallamount of comonomer components may be copolymerized, as the caserequires.

[0036] The comonomer components are monomers copolymerizable withtetrafluoroethylene and ethylene and may, for example, be the followingcompounds.

[0037] Fluorine-containing ethylenes such as CF₂═CFCl and CF₂═CH₂;

[0038] fluorine-containing propylenes such as CF₂═CFCF₃, and CF₂═CHCF₃;

[0039] fluorine-containing alkylethylenes wherein the carbon number inthe fluoroalkyl group is from 2 to 10, such as CH₂═CHC₂F₅, CH₂═CHC₄F₉,CH₂═CFC₄F₉, and CH₂═CF(CF₂)₃H;

[0040] perfluoro (alkylvinyl ethers) such as CF₂═CFO(CF₂CFXO)_(m)R_(f)(wherein R_(f) is a C₁₋₆ perfluoroalkyl group, X is a fluorine atom or atrifluoromethyl group and m is an integer of from 1 to 5);

[0041] vinyl ethers having a group which can readily be converted to acarboxylic acid group or a sulfonic acid group, such asCF₂═CFOCF₂CF₂CF₂COOCH₃, and CF₂═CFOCF₂CF (CF₃ )OCF₂CF₂SO₂F.

[0042] The molar ratio of ethylene/tetrafluoroethylene in ETFE ispreferably from 40/60 to 70/30, more preferably from 40/60 to 60/40. Thecontent of comonomer components is preferably from 0.3 to 10 mol %, morepreferably from 0.3 to 5 mol %, to the total monomers.

[0043] Specifically, the chlorotrifluoroethylene type resin may, forexample, be a chlorotrifluoroethylene homopolymer (CTFE) or anethylene/chlorotrifluoroethylene copolymer (ECTFE).

[0044] In the present invention, a mixed type resin containing the abovefluorine-containing resin as the main component and having otherthermoplastic resin incorporated, may also be preferably employed.

[0045] The thermosetting synthetic resin may, for example, be a melamineresin, a phenol resin, a urea resin, a furan resin, an alkyd resin, anunsaturated polyester resin, a diallylphthalate resin, an epoxy resin, asilicon resin, a polyurethane resin, a polyimide resin or apolyparabanic acid resin.

[0046] The form of the synthetic resin substrate to be used in thepresent invention, is not particularly limited. A substrate of a filmform, a sheet form or a plate form is preferred.

[0047] The thickness of the synthetic resin substrate havinghydrophobicity to be used in the present invention is preferably thinfrom the viewpoint of visible light transmittance. On the other hand, itis preferably thick from the viewpoint of the strength. Accordingly, thethickness is preferably from 10 to 300 μm, more preferably from 30 to200 μm.

[0048] The synthetic resin molded material of the present invention hasexcellent hydrophilicity imparted as the specific oxide thin film isformed by a dry method, and has good adhesion to the substrate, wherebythe affinity to various adhesives will be improved, and when laminatedon other synthetic resin or metal by means of such an adhesive, alaminate having a strong bonding force can be obtained.

[0049] Or, it is possible to coat on the synthetic resin molded materialof the present invention various treating agents which used to be hardlycoated directly on asynthetic resin substrates. Accordingly, variousfunctional films can be formed, and it is possible to obtain syntheticresin molded materials having various functions and excellent adhesiondurability. Such various functions include, for example, a drop flowingproperty, an ultraviolet ray insulating property, an antistatic propertyand an antibacterial property.

[0050] Further, with various catalytic functions represented by thephotocatalytic function, it is possible to impart an anti-soilingproperty or an antibacterial property.

[0051] The synthetic resin molded material of the present invention maybe used, for example, for windows for show casings, meters, vehicles,houses or buildings, blinds, wall papers, bath tubs, interior walls ofbath rooms, interior walls of kitchens or ceiling of gas ovens, or forpackaging materials, goggles, lenses for eye glasses, mirrors, curvemirrors or parabola antennas. It is particularly useful for applicationto covering materials for agricultural and horticultural houses(film-covering type houses or hard plate covering type houses).

BEST MODE FOR CARRYING OUT THE INVENTION EXAMPLES Example 1

[0052] As a synthetic resin substrate, an ETFE film (thickness: 60 μm)was prepared. In a sputtering apparatus, a substrate having the abovefilm of 10×10 cm fixed on a glass plate of 10×10 cm, was set on an anodeside, and a target made of a mixture of Si and Sn (atomic ratio of50:50) (hereinafter referred to as target A) was set on a cathode side.

[0053] The interior of the apparatus was evacuated to about 10⁻⁶ Torr ,and then argon and oxygen were introduced into the apparatus at a flowrate ratio of 1:4 to adjust the sputtering gas pressure to 5×10⁻³ Torr.

[0054] Using a direct current power source, sputtering was carried outat a power density of 2.75 W/cm² to form a thin film (film thickness;about 30 nm) of oxides of Si and Sn on the film surface, to obtain asynthetic resin molded material.

[0055] To examine the degree of hydrophilicity of the surface layer ofthe obtained synthetic resin resin molded material, the contact angle ofthe film surface to water (hereinafter referred to simply as a contactangle) was measured, and the result (the initial contact angle) is shownin Table 1.

[0056] Further, to measure the film-forming speed, film forming wascarried out under the same condition as the above film forming conditionexcept that only glass was set on the anode side and the power densitywas changed to 5.5 W/cm². The measured film forming speed of the thinfilm of an oxide, is shown in Table 1.

[0057] Further, formation of thin films of oxides were carried out invarious film thicknesses to examine the minimum film thickness at whichthe contact angle to water of the film thickness of 30 nm could bemaintained. The results are shown in Table 1.

Example 2

[0058] The operation was carried out in the same manner as in Example 1except that the direct current power source in Example 1 was changed toa radio frequency power source. With respect to the obtained syntheticresin molded material, various measurements were carried out in the samemanner as in Example 1, and the results are shown in Table 1.

Example 3

[0059] The operation was carried out in the same manner as in Example 2except that the target in Example 2 was changed to a Si target(hereinafter referred to as target B). With respect to the obtainedsynthetic resin molded material, various measurements were carried outin the same manner as in Example 1, and the results are shown in Table1.

Example 4

[0060] The operation was carried out in the same manner as in Example 1except that the target in Example 1 was changed to a target made of amixture of Si and Sn (atomic ratio of 65:35) (hereinafter referred to astarget C). With respect to the obtained synthetic resin molded material,various measurements were carried out in the same manner as in Example1, and the results are shown in Table 1.

Example 5

[0061] The operation was carried out in the same manner as in Example 1except that the target in Example 1 was changed to a target made of amixture of Si and Ti (atomic ratio of 50:50) (hereinafter referred to astarget D). With respect to the obtained synthetic resin molded material,various measurements were carried out in the same manner as in Example1, and the results are shown in Table 1.

Example 6

[0062] The operation was carried out in the same manner as in Example 1except that the target in Example 1 was changed to a target made of amixture of Si, Sn and Ti (atomic ratio of 50:35:15) (hereinafterreferred to as target E). With respect to the obtained synthetic resinmolded material, various measurements were carried out in the samemanner as in Example 1, and the results are shown in Table 1.

[0063] As shown in Table 1, the initial contact angles of Examples 1 to6 are equal, whereby it was confirmed that all of them have equalhydrophilicity. As compared with the case where target B of Example 3was used, the film forming speed was 5 times in a case where filmformation was carried out by a direct current sputtering method usingtarget A of Example 1, and twice in a case where film forming wascarried out by a radio frequency sputtering method using target A ofExample 2.

Example 7

[0064] The following experiment was carried out to examine thedurability of hydrophilicity of the surface layer of the synthetic resinmolded material having the oxide thin film layer of the presentinvention, i.e. to examine the drop flowing property, the durability ofthe film, the adhesion and the weather resistance.

[0065] In Example 7, the operation was carried out in the same manner asin Example 1 except that using target A, after evacuating the interiorof the sputtering apparatus to 3×10⁻⁵ Torr, argon and oxygen wereintroduced into the apparatus at a flow rate ratio of 1:4 to adjust thesputtering gas pressure to 2.4×10⁻³ Torr, and film formation was carriedout at a power density of 2.2 W/cm² to form a thin film (film thickness:about 6 nm) of oxides of Si and Sn, to obtain a synthetic resin moldedmaterial.

[0066] With respect to the obtained synthetic resin molded material, atest for the durability of hydrophilicity was carried out. The testapparatus was such that the opening of a constant temperature water tankof 80° C. was closed with the resin molded material so that the oxidethin film side of the resin molded material was located on the watertank side, and the exterior temperature was controlled to be 23° C. Inthis apparatus, the oxide thin film was exposed to saturated steam at80° C., and the time until the hydrophilicity was lost and the moisturecondensation was formed, was examined.

[0067] Further, to examine the adhesion durability between the oxidethin film and the substrate, a wiping test was carried out. In thewiping test, the thin film surface was wiped with a gauze, and thenumber of wiping operations until the hydrophilicity was lost, and themoisture condensation was formed on the thin film surface, was measured,and the film condition was observed.

[0068] Further, to examine the heat resistance of the synthetic resinmolded material, a heat cycle test was carried out. The conditions weresuch that one cycle consisted of two hours at 80° C., then one hour at20° C., then two hours at −30° C. and then one hour at 20° C., and theevaluation was carried out by the number of cycles until thehydrophilicity of the oxide thin film surface was lost.

[0069] Further, to examine the weather resistance of the oxide thinfilm, ultraviolet radiation for 500 hours and outdoor exposure test fortwo years were carried out, whereupon the presence or absence ofhydrophilicity was examined.

[0070] The results of the foregoing tests are shown in Table 2.

Example 8

[0071] The measurement and examination were carried out in the samemanner as in Example 7 using, instead of the oxide thin film in Example7, a silica thin film formed by coating an ethanol dispersion (solidcontent concentration=15 wt %) of a mixture comprising colloidal silica(OSCAL, manufactured by Shokubai Kasei Kogyo K.K.),β-(3,4-epoxycyclohexyl)ethyltrimethyoxysilane and polyoxyethylene-laurylether (solid content weight ratio=80:10:10). The results are shown inTable 2.

[0072] As shown in Table 2, Example 8 as a comparative example wasinferior to Example 7 in the durability of hydrophilicity, the adhesiondurability and the weather resistance. TABLE 1 Example 1 Example 2Example 3 Example 4 Example 5 Example 6 Initial contact ≦4 ≦4 ≦4 ≦4 ≦4≦4 angle (°) Film forming 120 50 25 100 30 85 speed (nm/min)Hydrophilicity 3 3 16 5 8 6 Minimum film thickness (nm)

[0073] TABLE 2 Example 7 Example 8 Durability Excellent hydrophilicitywas Hydrophilicity was lost in of hydro- maintained even afterexpiration 10 days. philicity of 12 months. Adhesion Excellenthydrophilicity was Hydrophilicity was lost in durability maintained evenafter 100 times. 3 times. Heat Excellent hydrophilicity wasHydrophilicity was lost resistance maintained even after at least after10 cycles. 100 cycles. Weather Excellent hydrophilicity wasHydrophilicity was lost by resistance maintained even after irradiationwith ultraviolet irradiation with rays, and a decrease ultraviolet raysor in the hydrophilicity outdoor exposure. was observed by outdoorexposure.

Examples 9 to 11

[0074] Evaluation was carried out in the same manner as Example 7 exceptthat the target in Example 7 was changed to C, D or E, whereby the sameresults as in Example 7 in Table 2 was obtained.

Industrial Applicability

[0075] The synthetic resin molded material of the present invention hassufficient hydrophilicity, and the hydrophilicity lasts for a longperiod of time, and at the same time, it is excellent in theproductivity. Further, it is excellent in the adhesion durabilitybetween the film and the substrate and also excellent in the weatherresistance, whereby it is useful for applications where durability isrequired.

[0076] Further, the synthetic resin molded material of the presentinvention is capable of effectively preventing moisture condensation.Accordingly, when it is used, for example, for an agricultural vinylhouse, it is possible to prevent such a drawback that incidence ofsunlight is prevented by moisture condensation, or water drops depositedon the resin surface will drop on crop plants without flowing along theresin surface.

[0077] Further, the synthetic resin molded material of the presentinvention has excellent hydrophilicity imparted, whereby affinity tovarious adhesives will be improved, and the adhesion to a substrate willbe excellent. Accordingly, it makes bonding to a substrate such as aresin having hydrophobicity, which used to be difficult to bond,possible, and it is thereby possible to provide a laminate having astrong adhesive force.

[0078] And, as compared with conventional coating film, desiredfunctions can be attained with a film thickness smaller by at least onefigure, whereby the required functions can be imparted without impairingtransparency or flexibility of the resin itself.

1. A synthetic resin molded material characterized in that a thin filmmade of an oxide of at least one metal selected from the groupconsisting of Si, Zr, Ti, Ta, Hf, Mo, W, Nb, Sn, In, Al, Cr and Zn isformed by a dry method on a synthetic resin substrate havinghydrophobicity.
 2. The synthetic resin molded product according to claim1, wherein said thin film is a thin film made of an oxide of a metalcontaining at least Si.
 3. The synthetic resin molded material accordingto claim 2, wherein said thin film is a film comprising SiO₂ as the maincomponent.
 4. The synthetic resin molded material according to claim 2,wherein said thin film is a thin film comprising oxides of Si and Sn asthe main components.
 5. The synthetic resin molded material according toclaim 2, wherein said thin film is a thin film comprising oxides of Siand Ti as the main components.
 6. The synthetic resin molded materialaccording to claim 2, wherein said thin film is a thin film comprisingoxides of Si, Sn and Ti as the main components.
 7. The synthetic resinmolded material according to any one of claims 1 to 6, wherein said drymethod is a sputtering method.
 8. The synthetic resin molded materialaccording to any one of claims 1 to 6, wherein said synthetic resinsubstrate is made of a fluorine-containing resin.
 9. The synthetic resinmolded material according to any one of claims 1 to 6, wherein saidsynthetic resin molded material is a covering material for anagricultural or horticultural house.
 10. A method for producing asynthetic resin molded material characterized in that an oxide of atleast one metal selected from the group consisting of Si, Zr, Ti, Ta,Hf, Mo, W, Nb, Sn, In, Al and Zn, is formed by a dry method on asynthetic resin substrate having hydrophobicity.